2016 Professional Engineer (PE) test preparation course; Nuclear and radiation technical disciplines

Takahashi, Naoki; Suzuki, Soju; Saito, Hiroto; Ueno, Takashi; Abe, Sadayoshi; Yamanaka, Atsushi; Tanigawa, Masafumi; Nakamura, Daishi; Sasaki, Shunichi; Mine, Tadaharu

Nihon Genshiryoku Gakkai Homu Peji (Internet), 20 Pages, 2017/05

no abstracts in English

Commentaries for third secondary national examination on fiscal 2010 for the professional engineer of nuclear and radiation; Commentaries (Part 2) including key point for elective examinations

Sasaki, Satoru; Suzuki, Soju; Nakano, Junichi; Takamatsu, Misao; Matoba, Ichiyo*; Nakano, Makoto*; Oketani, Koichiro*; Natsume, Tomohiro*

Genshiryoku eye, 57(2), p.66 - 75, 2011/02

http://ci.nii.ac.jp/naid/40017428113

no abstracts in English

Development of fast breeder reactor technology in Japan; Exploring substainable energy source for the next millennium

Suzuki, Soju

Gijutsushi, 20(9), p.16 - 19, 2008/09

http://www.engineer.or.jp/dept/nucrad/open/materials/suzuki200809.pdf

In view of the long-term energy security, the global warming prevention, the recent rapid rise of oil price etc., the time of Nuclear Power Renaissance has just come worldwide and the FBR is spotlighted again as a perspective technology leading the Renaissance. The Japan's approach to the commercialization of FBR is described briefly in this paper.

Core performance tests for the JOYO MK-III upgrade

Aoyama, Takafumi; Sekine, Takashi; Maeda, Shigetaka; Yoshida, Akihiro; Maeda, Yukimoto; Suzuki, Soju; Takeda, Toshikazu*

Nuclear Engineering and Design, 237(4), p.353 - 368, 2007/02

https://doi.org/10.1016/j.nucengdes.2006.07.003

Many changes were made in the recent upgrade of the experimental fast reactor JOYO to the MK-III design. The core changes which were made to achieve a fourfold increase in irradiation capacity include the introduction of a second enrichment zone, an increase in core radius and a decrease in core height. Performance tests done at low power, during the rise to power, and at full power, which focus on the neutronics characteristics, are presented. These tests include the nuclear instrumentation system response, the approach to criticality and excess reactivity evaluation, control rod worth calibration, isothermal temperature coefficient evaluation, the calibration of the nuclear instrumentation system with reactor thermal power, and the burn-up reactivity coefficient evaluation. The measurements and comparisons with calculated predictions are shown. The design predictions are consistent with the performance test results, and all technical safety specifications are satisfied. The JOYO MK-III core will provide enhanced irradiation testing capability, as well as serve as a test bed for improving fast reactor operation, performance and safety. Through the performance test evaluation, the core characteristics of a small size sodium cooled fast reactor with a hard neutron spectrum are clarified.

Transmutation of technetium in the experimental fast reactor "JOYO"

Aoyama, Takafumi; Maeda, Shigetaka; Maeda, Yukimoto; Suzuki, Soju

Journal of Nuclear and Radiochemical Sciences, 6(3), p.279 - 282, 2005/12

https://doi.org/10.14494/jnrs2000.6.3_279

The present study examines the potential for the demonstration of fission product transmutation in the experimental fast reactor JOYO at JNC's Oarai Engineering Center. The possibility of creating a highly-efficient transmutation irradiation field by loading neutron moderating subassemblies in the reflector region of JOYO was examined in a series of scoping calculations. A cluster of reflector subassemblies was replaced with beryllium or zirconium hydride (ZrH1.65) moderated subassemblies. These moderated subassemblies surrounded one central test subassembly that would contain Tc or I target material. The Tc transmutation rate was 16.2% using ZrH and 13.9% using beryllium as moderator. As a result of this study, basic characteristics of LLFP transmutation in JOYO using relevant moderator materials were investigated and the future feasibility was shown.

None

Suzuki, Soju

Nihon Kikai Gakkai Doryoku Enerugi Shisutemu Bumon Nyusu Reta, (31), p.3 - 6, 2005/10

ACROSS (Accurately Controlled Routinely Operated Signal System) is a method to investigate any change of physical state in the Earth's interior using accurately controlled seismic ans/or electromagnetic sources. We preliminary obtained Pg, Sg, and possible plate boundary reflected PxP phase using one-moth long stacking data up to nearly 70 km distance. The seismic reflection experiment across the central Japan revealed the strong PxP reflection phase from 30-40 km deep of the Philippine Sea Plate boundary around the Tokai Region, Japan (Iidaka et al., 2003). The same seismic exploration line crossed the area where many active faults distribute. One of the big issues for revealing the loading process for active faults is to examine the process in the lower crust around active faults. To examine the seismic exploration records obtained by Iidaka et al. (2003), we noticed the presence of strong phases, which can be explained as PxP reflection from the plane at 20 km deep around the Atera fault, which is one of the most active faults in Japan. The phases are identified by a number of explosions on the survey line from north to south of this region. One of high possibilities for the 20 km reflector is the detachment in the lower crust. The high velocity contrast can explain such PxP reflection phase. We evaluated the possibility to observe such phase by the ACROSS transmission from the present source located in Toki city and may conclude to be able to observe such phase and its temporal change, if the seismometers are placed 50-100 km distance north of this region. We also generated synthetic seismograms to confirm the detection. In addition to seismic ACROSS, electrometric ACROSS method may identify the strong-reflection source and its temporal change using resistively analysis around the Tokai Region, Japan. This approach can give high possibility to watch the change of physical state beneath the active faults and it may contribute for the earthquake forecasting.

JOYO MK-III, state-of-the-art, FBR Irradiation Test Facility

Hara, Hiroshi; Nagata, Takashi; Aoyama, Takafumi; Suzuki, Soju; Nagata, Takashi

Proceedings of 14th Pacific Basin Nuclear Conference (PBNC-14), 0 Pages, 2004/00

Focusing on the cover layer materials (as the Radon Barrier Materials), which could have the effect to restrain the radon from scattering into the air and the effect of the radiation shielding, we produced the radon barrier materials with crude bentonite on an experimental basis, using the rotary type comprehensive unit for grinding and mixing, through which we carried out the evaluation of the characteristics thereof.

Operation and Upgrade experiences in the Experimental Fast Reactor JOYO

; Maeda, Yukimoto; Suzuki, Soju; Hara, Hiroshi

Russian Forum for Sci. and Tech. FAST NEUTRON REAC, 0 Pages, 2003/00

The experimental fast reactor JOYO attained its initial criticality in 1977 with the MK-I breeder core. In 1982, JOYO was modified to the MK-II irradiation core and finished its operation in 2000. Throughout the successful operation of MK-I and MK-II core, the net operation time has exceeded 60,000 hours, and experience on the operation, maintenance and core/fuel management of a fast reactor plant has been accumulated. Furthermore the MK-III modification program is underway to improve the irradiation capability of JOYO. When the MK-III core is started, it will support irradiation tests in feasibility studies for fast reactor and related fuel cycle research and development in Japan.

Glorious achievement of a quarter century operation and a promising project named MK-III in JOYO

Maeda, Yukimoto; Aoyama, Takafumi; Odo, Toshihiro; Nakai, Satoru;

P96, 96 Pages, 2002/00

None

Reactivity measurement in the JUPITER experiment and Its accuracy

; Aoyama, Takafumi; ; Shirakata, Keisho

JNC TN9400 2001-032, 57 Pages, 2001/01

JNC-TN9400-2001-032.pdf:1.53MB

This report describes the reactivity measurement method and its accuracy employed in ZPPR (Zero Power Physics Reactor) test facility at Argonne National Laboratory, USA. In ZPPR, reactivity measurements were conducted by means of MSM (Modified Neutron Source Multiplication) method using the fission reaction rates by 64 U fission chambers which were uniformly located in the core region. The MSM method can evaluate the subcritical reactivity considering the spatial distribution of neutron flux, although its basic equation is the one point approximation reactor dynamic theory. As each detector response varies depending on the core configuration, the uncertainty of the detector response affect directly the accuracy of measured reactivity. Therefore, the average value of many detectors had been conventionally used to reduce the statistical error in the measurerment. In this study, this method was modified to use the linear fitting between measured reaction rates and detector responses. Using this modified method, the uncertainty of each detector response affect the measured reactivity less than the simple averaging method. This new method was verified by applying to the ZPPR control rod worth measurements. It was found that the ratios of neutron source intensities and detector responses could be corrected accurately by the linear fitting in case of reactivity change without or with little fuel movement such as a unit control rod worth measurement.